Portable coolers are commonly used in a number of different applications. In a number of cases, the methods to cool items inside a portable cooler are messy, expensive, and/or inefficient. For example, ice can be used in portable coolers to keep food and drinks cold. Ice can be obtained from the refrigerator, freezer, or purchased at a neighborhood convenience store, gas station, or grocery store. After use, the melted ice is purged from the cooler and the remaining ice is discarded. Some of the problems with using ice include the fact that melted ice can spoil food items such as sandwiches and snacks as it melts; as drinks are consumed, a user must dig through cold ice to “fish” out his or her beverage, causing cold discomfort on the hands and arms; ice cubes or chunks of ice melt at a faster rate than one large mass of ice; and ice is not common or readily available outside the U.S.A.
Reusable freezer blocks, soft ice packs, gel packs, and ice sheets are common alternatives to ice. Some are pre-filled with freezable gel while others are filled with tap water. Typically these are tossed in and around the inside of the cooler or in the case of a soft-sided cooler, an ice pocket is sewn to the underside of the cooler lid. Some of the problems associated with the use of freezer blocks include the fact that current freezer blocks, gel packs or other ice alternatives are placed inside the cooler in-between food and beverages taking up valuable space inside the cooler; the ice blocks and ice alternatives rattle around and fall over inside the cooler without the ability of being strategically located for optimum performance. Furthermore, some coolers have been developed with snaps or toggles to locate ice blocks to the underside of the cooler lid. In this instance, the cooling block is above the food and drinks and natural physics of heat rising diminishes the ability of the ice block to cool the contents of the cooler. Furthermore, heat and thermal conduction from the cooler lid causes the ice block to melt faster, perspire and drip condensation onto food and drinks resulting in the same issue as was caused with melted ice.
There are also Thermoelectric (TE) coolers that are powered by an AC or DC source and combine mechanical parts such as fans, heat sinks and solid state technology referred to as a Peltier cooling system. The Thermoelectric Cooler is also known as an “iceless cooler”. Some of the problems typically associated with TE coolers include the fact that coolers are mostly used outdoors where electricity is not available; coolers are typically designed to be portable and carried from the home or auto to another destination, and the mechanical components of the TE cooler add significant weight making it less portable; TE coolers chill based on the performance of the Peltier system and the surrounding ambient temperature and current embodiments used on a hot sunny day of 95 degrees Fahrenheit can only reduce the temperature inside of the cooler to about 55-63 degrees Fahrenheit, well above a thirst satisfying temperature range; and TE coolers are typically four times the cost of passive or traditional coolers of equivalent size.